Combined air compressor and motor.



D. E. CROUSE, G. G. EIDSON & T. DAVIS. COMBINED AIR COMPRESSOR ANDMOTOR.

APPLIOATION IILBD JUNE a, 1013.

1,105,494. Patented July 28, 1914,

2 SHEBTS-SHEET 1.

INVHJTORS' WITNESSES 4 5 6W 6W? 5%? (F y/aof/zw ficzazi? In &0,

ATTORNEYS D. B. OROUSE, U. G. EIDSON & T. DAVIS.

COMBINED AIR COMPRESSOR AND MOTOR.

APPLICATION FILED JUNE 6, 1913.

,105A94. Patented July 28, 1914; I Q g 2 SHEETSSHEET 2.

TNESSES ATTORNEYS ltlhl ddthttd PA Fl OE.

DAVID E. CROUSE AND CHARLES G. EIDSQN, 01F ANNAPOLIS, MARYLAND, ANDTHOMAS DAVIS, OF WILKINSBURG, PENNSYLVANIA, ASSIGNORS TO THE AUTO AIRAPPLI- ANGIE COMPANY, OF BALTIMORE, MARYLAND, A CORPORATION OF MARYLAND.

COMBINED AIR COMPRESSOR AND MOTOR.

Liltltifttld.

To all whom it may concern Be it known that we, DAVID E. Cnonsn andCHARLES G. Ellison. citizens of the United States, and residents ofAnnapolis. in the county of Anne Arundel and State of li laryland, andTIIUHAS l) \vis.'a citizen of theUnited States, and a resident ofWilkinsburg. in the county of Allegheny and State of Pennsylvania, havemade certain new and useful Improvements in Combined Air Compressors andMotors, of which the following is a specification.

()nr invention relates to improvements in combined air compressors andmotors. and it consists in the combinations. constructions, andarrangenwnts herein described and claimed.

An object of our invention is to provide a device which may be usedeither as a means for con'ipressing air or as a motor.

It is particularly. adapted for use as a starting device forautomobiles, and also as a means for conn'n'cssing air for driving thestarting device.

A further object of our invention is to provide a device of the natureinscribed having valves which are brought into play when the device isused as a motor, but which are put out of operation when the device isused as a compressor. thereby rein dering the life of the valvemechanism of greater duration than it would otherwise be.

A furthenobject of our invention is to provide a device having a novelform of valve mechanism for aecom 'ilishing the above named objects,

Other objects and advantages will appear in the following specificationand the novel features of the invention will he particnlarly pointed outin the appended claims.

Our invention is illustrated in the accompanying drawings forming partof this application in Which- Figure 1 is a plan view of the device,Fig. 2 is a vertical section through the device showing the valves intheir normal position when the device is used as a compressor, Fig. 3 isa face View of one of the cams, Fig. 4 is a fragmentary section alongthe line 4-4 of Fig. 1, Fig. 5 'is a view similar to Fig. 2 showing thevalves in one of the positions which they assume when the device isbeing used as a motor, Fig. 6 is a detail View of one of the checkvalves,

Specification of Letters Patent.

Application filed June 6, 1913.

llntentcd July 28, 1914.

Serial No. 772,079.

and Fig. 7 is a plan view of the valve shown in Fig. (3.

in carrying out our invention we provide a base 1. upon which is mounteda casing 2 (see Fig. 1) having a plurality oi cylinders such as thoseshown at A. B. (l and .1). Each of the cylinders is provided with apiston as A. ll. (1 and l). Secured to the upper part of the casing 2 isa valve casing 23. which extends above the cylinders. At one end of thevalve casing is a cylindrical chamber -l-, while at the other is asimilar chamber l. The chamber 4 has a reduced extension 5. a similarextension 5- being provided "for the chamber 4. partition (5 separatesthe chambers 5 and 5" and this partition has a central opening' (3.Within the valve chamber t is a piston valve 7 which is secured to avalve stem 8. At one end of the valve stem 8 is an auxiliary pistonvalve 5) which is disposed in the extension 5 of the chamber 4. Betweenthe partition (l and the auxiliary piston valve J is a spiral spring 10.Disposed within the chamber -t is a hollow cylinder ll. One end ot thecylinder is closed by a head 12 having an integral nut; 1;) which isscrewed on an extension ll of the stem or rod 8. A passage 15 extendsfrom the end of the extension which is within the cylinder 11 andterminates at an opening 16 in the stem or rod 8.

The cylinder ll is provided with an ex tension 11" which is arranged toslide through the end of the valve casing fl, piston 17 is disposedwithin'the cylinder ll and is provided with a stem or rod 18 whichextends through the portion 1 and is arranged to be engaged by the arm19 ot' a bellcrank lever which is pivoted at 30. and which is providedwith :1 depending arm 91, which has a pivotal connection at 22 to thebell-crank lever. The arm 21 is arranged to be engaged by a cam 23 onthe crank shaft 24. ()n the other side of the partition (1' are thepiston valves 7" and 9, the cylinder 11", the piston 17" and the othercooperating parts which are precisely simi lar to those alreadydescribed. Each cylinder is provided with an air inlet such as thatshown at (1, I). c and (I, which is controlled by a valve like thatshown in Figs. (3 and 7. This valve has a body portion or havingradially extending lugs v. The

Ilia

body portion is recessed as shown at '0 and a spring ,9 is disposed inthis recess and is arranged to engage a bearing plate 7 which caps thecylinders, An opening p is provided in the bearing plate. The spring tkeeps the valve normally in the position shown in Fig. 6. but when theair is eX- hansted within one of the cylinders A, B, C or D, the excesspressure of the atmosphere will push the valve downwardly and passaround between the lugs v and through the ports 7) into the cylinder. The valve prevents any escape of the air from the cylinder through theinlet ports 7) and a. Arranged to establish communication between eachof the cylinders and the interior of the valve casing 3 are ports a, a6', b 0, c and d. (F. Intake ports 25, 25 and 25 are provided in thevalve casing.

In the rear oi the valve casing 3 are the check valves such as thatshown at 26 in Fig. l. There is one of these check valves to eachcylii'ider A, B, C and D. These valves permit the passage of air out ofthe cylinders, but prevents the return of air to the cylinders. A. pipe27 having branches 2? is arranged to convey the air forced from thecylinders to a common reservoir (not shown) where the air may be storedunder pressure. El pipe 28 provided with a cut-oil valve (see Fig. 9) isarranged to communicate with the interior of the valve casing 53, bymeans of branch pipes 30 and 30 respectively. llhecranl; shaltQ-l isconnected to the pistonsas shown in Fig. 2. The pistons A am ll areconnected at 180 apart, the pistons C and D at. 180 apart, and thepistons C and ll at 90 apart.

From the foregoing description of the various parts of the device theoperation thereof may be readily understood. \Vhen the device is to beused as an air comprcssor the valve 29 (see Fig. 2) is closed. Thevalves 7, 9, '7 and 9 are in a position to cover the ports it. tai 5',Z2 0', 0 and (Z, d respectively. We will show later how the valves arebrought to this position. Power is applied to the crank shaft. 24; inany suitable manner and the revolution of the crank shaft causes thereciprocation of the pistons A, B, C and D. Consider the piston It. i Itis just at the end of its travel in the direction indicated by the arrowin Fig. Air is being forced out of the cylinder rt past the check valve26 (see his". 4:) and into the common pipe 27 leading to the reservoir(not shown). The pistion it is drawing air through the opening 26 andpast the check valve U in the inlet t). l i ng air out. into the .i nopiston k common reservoir and the. piston I)" is drawing air throt iithe inlet 25 and past the valve ein t-b nlet opcni tal. Theoperatmn 3 ofan ordinary t the-n. the device thus l ar air pump or i l is runningr asan air pump, the small springs l and 7r hold the bell-crank levers l9and 19- in such a position asto raise the rods 21 and 21 so that. thehighest part of the cams 23 and 23, 0., the part 23 shown in Fig. 3.will just graze the lower end of the rod. There will therefore be nomovement of the piston rods 18' and 18 (see Fig. 2) which are engaged bythe bellcrank levers 19 and 19 respectively, after each piston rod hasbeen pushed inward to the position where all the ports a, a Z), etc. arecovered. Now when it is designed to run the device as a motor the valve29 is opened to permit the air to enter from any source of compressedair (not shown). Consider now the conditions when the air enters thechamber 5 in Fi 5 through the i e 30.

h P l and that the low part '23 of the cam 23 is up and the high part 23of cam 23 is up. llhe area of the piston valve 7 is greater than thearea of the piston valve 9 and hence the two valves will move to theright. in Fig. 5, but since the cylinder ll is rigidly socured to thevalve stem it will also move to the right. Furthermore, air enteringthrough the opening 16 and passing along" the passage 15 will force thepiston 17 to the cud of the cylinder 11 and Will therefore move the.contact rod 18 outwardly. The rod 18 which is in contact with thebell-crank lever 15.) will rotate the latter on its pivot so as to forcethe rod 21 down wardly into the path of the rotating cam 23. Themovement of the piston valves 7 and U to the right in Fig. o will causethem to cover the ports a and I) and to uncover the ports (1 and b".Compressed air will enter through the poi-ta and drive the piston .l' inthe direction shown by the arrow (Fig. 5). 'lhe piston i3 is running: inthe direction shown by the arrow and the port 6* will serve as anexhaust port to permit the air to pass through the space between thepiston valves 9 and 9 and out at the opening 259'.

It will be understood that the ilves T and l) in Fig. 5 cover the portsoz and :5 only when the cam rod 21 (see Fig. is on the lower portion 23(see 3) e ll hcn, however, the surface which is the higher surface ofthe can, engages the rod 2i it will tend to rotate the bell-crank lever19 so as to force the st in i8 inwardly. lv'oiv the space between the on1? and the head 12 of the cylinder 'ed by comthe rod 18 A QM.

prt ed air, and therefore moves nnvardly it will me e cylinder ll acdalso the valves 7 and S) l a the pres ol the air. because the t ated.occurs at the EC pistons "a is inert;

positively moment of m 2. il 1% Lil t ip ward l y the a. is opened.asced through the port a and through the chamber 4 at the outlet Whenthe valve 9 uncovers the port I) and covers the port 6 pressure willenter through the port I) and force the piston B downwardly. Since thehigh surfaces on the cams 23 and 23 are 180 apart it therefore followsthat while the valves 7 and 9 are moved to the right by the pressure ofthe air coming in from the reservoir through the pipe 30 the pistonvalve 7 x and 9 are also moved to the right bythe fact that the cam 23has moved the cam lever 19 so as to positively force the stem 18inwardly and thereby moving the cylinder 11 and the valves 7" and 9 asdescribed. This condition is shown in Fig. ,5, so that in Fig. 5pressure is entering from the pipe 30 and passing through the ports 0thus driving the piston C downwardly. The piston D is forcing air outfrom the port d and through the exit port 25, When air is admittedthrough the passages 15 or 15 into the interior of the cylinders so asto provide a cushion, the compressed air between the head. of thecylinder and the small piston 17 or 17 contained in these cylinders, theeffect is to thrust the piston stems 18 or 18 outwardly into the path ofthe vibrating bell-crank levers 19 and 19. This will permit the levers19 and 19 to move the valves 7, 9, 7 and 9" so as to uncover one ort andto cover theother alternately. n other words, it will give a full throwto the valves.

When, however, the valve 29 is closed, while the motor is still runningthe pistons Will' keep on working as long as there is momentum in thefly wheel (not shown). Thus the pressure in the chambers 5 and 5* willrapidly lower, the pressure will be relieved from the interior of thecylinders 11 and 11 and the pistons 17 and 17 will be permitted to comein contact with the extension 14 of the valve stem, the travel ofpistons 17 and 17- in the cylinders 11 and 11* respectively bcin, equalto half of the total valve travel.

Now when the bell-crank levers 19 and 19 are forced inwardly by the camsthe istons 7, 9, 7 and 9* will be only moved h f a stroke so as to bringthem into the position shown in Fig. The effect is the simeas if therods 18 and 18 had been suddenly shortened. The springs 10 and 10 are ofjust sutlicient length to force the piston valves outward from thecenter to a position covering all ports. and the shortening of the stems18 and 18 (by air being removed from the cylinders 11 and 11) causes thecam action to force the piston valves in toward the center to positioncovering all the ports. The springs and In will cause the bell-cranklevers 19 and 19 to lift the rods 21 and 21*, as described, so that whenthe device is used as a pump the sliding valves will be out ofcommission entirely. There is therefore no wear on these sliding valveswhile the device is being used as a pump. As the device is bcing used asa pump the greater part of the time it will be readily seen that thereis very little wcar indeed on these sliding valves. urthcrmorc by meansof springs in and it the rods 21. and 21 are held up out of the path ofthe cams.

From the above description it will be seen that the opening or closingof the cock 2!) Virtually changes this device from a motor to an aircompressor or vice versa and that the mechanism described automaticallyadjusts itself so as to reduce the wear on the parts.

We claim:

1. In a combined air motor and compressor, a plurality of cylinders eachprovided with an inlet check valve and an outlet check valve, and aninlet port and an outlet port, a valve casing common to all of saidcylinders, slide valves in said valve casing for controlling the portsof each cylinder, and means for shifting said slide valves toalternately cover and unwver said inlet and sa d outlet ports when thedevice 15 used as a motor, the shutting oil of the motive fluid servingto permit the valveactuating devices to move the valve so as to coverall of said. ports.

2. In a combined air motor and com pressor, a cylinder, a pistontherein, said cylinder having an inlet check valve and an outlet checkvalve, and an inlet port and an exhaust port, a valve casing, a pistonvalve disposed within said valve casi-ng for controlling said ports, anauxiliary cylinder disposed within said valve casing. said cylinderhaving a rigid connection with said piston valve, an auxiliary pistonwithin said auxiliary cylinder, a piston rod or stem connected to thesaid auxiliary piston and arranged to project through said valve casing,means for supplying lluid, pressure in the interior of said auxiliarycylinder, and movable means outside of said, valve casing for engagingthe end of said auxiliary piston rod for moving the latter.

3. In a combined air motor and compressor, a crank shaft, a cam on saidcrank shaft, a cylinder, apiston within said. cylinder arranged to beoperated by said crank shaft, said cylinder having an inlet check valveand an outlet check valve, and an inlet port and an exhaust port, avalve casing, a piston valvc lisposcd within said valve casing forcontrolling said ports, an auxiliary cylinder disposed within said valvecasing, said cylinder having a rigid connection with said piston valve,an auxiliary piston within said auxiliary cylinder, a piston rod or stemconnected to the said auxiliary piston and arranged to project throughsaid valve casing, means for supplying fluid pressure in the interiorof'said auxiliary cylinder, movable means outside of said valvecasingfor engaging the end of said auxiliary piston rod for moving thelatter, said last named movable means comprising a bell-crank lever, oneend of the bell-crank lever being in the path of said auxiliary pistonstem, and a cam rod pivotally connected with the other end of thebell-crank lever and arranged to be engaged by the cam on said crankshaft.

4. In a combined air motor and compressor, a cylinder, a piston therein,an inlet check valve and an outlet check valve for said cylinder, saidcylinder also having an inlet port and an exhaust port, a valve casing,a piston valve Within said casing for controlling said ports, a'reciprocating member disposed outside of said valve casing, a rodarranged to extend through the end of said valve casing in the path ofsaid reciprocating member for moving said piston valve, and means forvarying the posi tion of the rod with respect to the reciprocatingmember, thereby varying the length of stroke of the piston valve.

5. In a combined air motor and compressor, amain cylinder, a pistontherein, said cylinder having an inlet port and an exhaust port, a valvecasing, a piston valve disposed within said casing for controlling saidports, said piston valve having a stem provided with a passage, anauxiliary cylinder disposed within said valve casing and having rigidconnection with said piston valve, the interior of said auxiliarycylinder having communication with said passage, a piston within saidauxiliary cylinder having a stem arranged to extend through one end ofsaid cylinder and outside the valve casing. a bell-crank lever arrangedto engage the end of the stem of said auxiliary piston, means forreciprocating. sald bellcrank lever, and means for admitting compressedair on one side of said piston valve, the passage of air into theinterior of said auxiliary cylinder servingto move said auxiliary pistonthereby extending the stem of the latter toward the reciprocatingmember.

6. In a combined air motor and compressor, a main cylinder, a pistontherein, said cylinder having an inlet port and an exhaust port, avalve'casing, a piston valve disposed within said casing for controllingsaid ports, said piston valve having a stem provided with a assage, anauxiliary cylinder disposed wlthin said valve casing and having rigidconnections with said piston valve, the interior of said auxiliarycylinder having communication with said passage, a piston within saidauxiliary c linder having a stem arranged to extend-t rough one end ofsaid cylinder and outside the valve casing,

a bell-crank lever arranged to engage the end of the stem ofsaidauxiliary piston, means for reciprocating said bell-crank lever, meansfor admitting compressed air on one side of said piston valve, thepassage of air into the interior of said auxiliary cylinder serving tomove said auxiliary piston thereby extending the stem of the lattertoward the reciprocating ,member, a second main cylinder having an inletand an exhaust port, and a piston valve for controlling the ports ofsaid second main cylinder, said last-named piston valve being secured tothe stem of said first-named piston valve, and its area being smallerthan that of the first-named piston valve.

7. In a combined air motor and compressor, a main cylinder, a pistontherein, said cylinder having an inlet port and an exhaust port, a valvecasing, a piston valve disposed within said casing for controlling saidports, said piston valve having a stem provided with a passage, anauxiliary cylinder disposed Within said valve casing and having rigid.connections with said piston valve, the interior of said auxiliarycylinder having communication with said passage, a piston Within saidauxiliary cylinder having a stem arranged to extend through one end ofsaid cylinder and outside the valve casing, a bell-crank lever arrangedto engage the end of the stem of said auxiliary piston, means forreciprocating said bell-crank lever, means for admitting compressed airon one side of said piston valve, the passage of air into the interiorof said auxiliary cylinder serving to move said auxlliary piston therebyextending the stem of the latter toward the reciprocating member. asecond main cylinder having an inlet and anexhaust port, a piston valvefor controlling the ports of said second main cylinder, said last-namedpiston valve being secured to the stem of said first-named piston valve,and its area being smaller than that of the first-named piston valve,and a crank shaft for operating the pistons in both of said maincylinders, said crank shaft having crank arms extending in oppositedirections, one of said crank arms being connected to the piston in oneof said main cylinders and the other crank arm being connected to thepiston in the other main cylinder.

DAVID E. CROUSE. CHAS, G. EIDSON. THOMAS DAVIS. Witnesses as to David E.Grouse and Chas. Gr. Eidson:

J. W. PHENMAN, M. C. SAUERWEIN. Witnesses as to Thomas Davis:

Jonn 'Ifisomson, WAL'I'ER K. ELDER.

